books.google.com - Travel backward through time from today's scattered billions to the handful of early humans who lived in Africa 60,000 years ago and are ancestors to us all. In Deep Ancestry, scientist and National Geographic explorer Spencer Wells shows how tiny genetic changes add up over time into a fascinating...http://books.google.com/books/about/Deep_Ancestry.html?id=1CBEwqfGf8gC&q=result&utm_source=gb-gplus-shareDeep Ancestry